U.S. Sen. Bernie Sanders and actor Danny Glover are coming to Mississippi to help bring attention to what organizers call poor working conditions at Canton's Nissan manufacturing plant, according to the Mississippi NAACP.

U.S. Rep. Bennie Thompson and Sierra Club President Aaron Mair will also attend.

The march focuses on attempts by Nissan workers to unionize and the intimidation they say they've faced in response.

"As we meet with workers, we see a heightened level of frustration and concern about the atmosphere and treatment at the plant," said Derrick Johnson, president of the Mississippi NAACP, which is helping organize the event. "Far too often we are receiving repeated complaints."

An emailed response from the company Tuesday said, "Nissan's history reflects that we truly value our employees and respect their right to decide who should represent them. Nissan Canton employees enjoy good, stable, safe jobs with some of the highest wages and strongest benefits in Mississippi. The allegations being made by the union against Nissan are completely unfounded."

In December, the Detroit-based United Auto Workers filed complaints in the Netherlands, Japan and France against Nissan, French automaker Renault, which partners with Nissan, and the joint corporation. It was the latest in a string of complaints Nissan has received over the past several years as Canton workers have tried to unionize.

The Dec. 20 press release announcing the complaints stated that a report based on interviews with workers, testimonies and documents from Nissan showed several violations on the part of the company.

"They include aggressive policies and practices of union avoidance, harassment and intimidation, which instill fear at work with the aim of preventing workers from securing union representation. For years, management at Nissan and Renault have repeatedly ignored calls from workers and policy-makers to use their powers to address these global human rights violations," the release states.

"They found slip hazards with oil and water on the floors and then they found an open pit, which is the repeat violation," Travis Parks told Mississippi Public Broadcasting. Parks is a production technician at the plant and member of a group seeking to unionize workers.

Parks said an open test pit is similar to that used at an oil change shop to work under vehicles. Parks says OSHA inspected the plant after a worker fell in a pit last October, and was hospitalized.

Workers filed a complaint after another employee fell into a pit in February 2016, and was also hospitalized. OSHA fined Nissan $32,000 for the repeated pit violation and water and oil on floors.